The present invention relates to connectors and, more particularly, to connectors used in fiber optic communication arrangements.
Connectors to attach pieces to an opto-electronic module exist, but in all cases, the size of the opto-electronic part chip in the module is smaller than the spacing between the alignment elements, for example, the guide pins used to ensure accurate, reproducible alignment between fibers in the connector and the module.
This prior art arrangement is shown in FIG. 1. A fiber bundle is terminated into a connector which contains a ferrule. The Connector-Ferrule combination performs two functions: It holds the individual fibers very accurately with respect to one another and it holds the multiple fibers, as a group, very accurately with respect to the particular alignment features so that when the connector is plugged into a mating connector (holding additional fibers or on a module), the two connectors align the fibers that are integrated with the first connector with the corresponding features (either fibers or optical or mechanical devices) that are integrated into the second connector.
In order to maintain high accuracy when plugging two connectors together, there are usually two or more alignment features that are spaced apart over some distance. However, to maintain the accuracy of these alignment features with respect to one another, they cannot be separated in space by too great a distance. This is because, when manufacturing parts with extreme accuracy, the manufacturing error in relative placement of the alignment features increases as those features get spaced further apart. Hence, the features need to be spaced far enough that they can control such things as X-Y positioning and rotation in that plane accurately enough, but not so far apart that the accuracy of the placement of those features themselves interfere with the accuracy of the connection.
For purposes of compatibility, the industry currently uses a few standard connectors, for example the MTP(copyright) connector (a registered trademark of US Conec Ltd). The MTP connector has two alignment or guide pins spaced 4.6 mm apart. As a result, the size of an opto-electronic part that can be used with this connector is limited by the spacing of the alignment or guide pins.
As time progresses, opto-electronic components or modules have begun to incorporate chips into having more and more optical devices and, in some cases, greater electronic functionality. However, as the numbers of devices and functionality increase, the chips get larger. Thus, the connector can become a limitation on the size of the chip (and hence the number of devices or amount of functionality).
Compounding the problem is the fact that, in modules currently available, the alignment features on the module side are integrated into the module package.
Presently, opto-electronic chips are or will imminently be larger than the spacing of the alignment features on the optical connector. Thus, as shown in FIG. 2, there is a problem with providing alignment features on the module side that meet the spacing criteria necessary to connect to currently available commercial connectors.
One possible solution to the problem is to design a wholly new connector for use with larger chips. However, connector design is expensive and typically outside the business areas of producers of the chips. Moreover, there is no way to guarantee widespread acceptance of such a connector, thereby limiting the market for both the chips and connectors. In addition, it is desirable for such larger chips to nevertheless be compatible with existing connectors, to avoid the problem of widespread rejection due to the inherent obsolescence effect it will have on existing products already in use.
Thus, there is a need for a way for chips larger than the alignment pin spacing to be able to be used with current commercially available connectors.
We have developed a mechanical connector piece which provides a way to attach a multi-fiber connector to an opto-electronic module when the size of the opto-electronic component (i.e. chip) for the module is larger in a real extent than the spacing of the high precision alignment elements (e.g. guide pins or other alignment features) used in commercial connectors.
The advantages and features described herein are a few of the many advantages and features available from representative embodiments and are presented only to assist in understanding the invention. It should be understood that they are not to be considered limitations on the invention as defined by the claims, or limitations on equivalents to the claims. For instance, some of these advantages are mutually contradictory, in that they cannot be simultaneously present in a single embodiment. Similarly, some advantages are applicable to one aspect of the invention, and inapplicable to others. Thus, this summary of features and advantages should not be considered dispositive in determining equivalence. Additional features and advantages of the invention will become apparent in the following description, from the drawings, and from the claims.